Multifunctional breath analyzer

Abstract

A multifunctional breath analyzer includes a receptor unit for receiving a breath sample from a test subject, a sensing unit providing a signal corresponding to the concentration of at least one volatile substance within the sample, elements for providing a signal indicative of the dilution of the breath sample, and an analyzing unit/processing unit for the identification and quantification of the volatile substance of the breath sample. The signal processing unit is configured to perform at least two different calculations for the quantification, and the signal processing unit is also configured to automatically display the result of a selected calculation, the selection being based on the signal indicating dilution.

The invention claimed is: 
     
       1. A dual mode breath analyzer, comprising:
 an enclosure ( 1 ); 
 a receptor unit ( 4 ) for receiving a breath sample from a test subject, the receptor unit including a first receptor unit ( 4   a ) having the shape of a funnel ( 4   a ), scoop, cup or mug for receiving the breath sample from the test subject with the dual mode breath analyzer operating in a contactless mode, and a second receptor unit ( 4   b ) having a tubular shape for receiving the breath sample from the test subject with the dual mode breath analyzer operating in a contact mode, 
 each of the first receptor unit and the second receptor unit being detachably securable to the enclosure ( 1 ) with the first receptor unit being detachably secured to the enclosure for the dual mode breath analyzer operating in the contactless mode and the second receptor unit being detachably secured to the enclosure for the dual mode breath analyzer operating in the contact mode, the contactless mode being a screening operational mode and the contact mode being an operational mode with a higher accuracy than the screening operational mode, 
 each of the first and second receptor units having a breath sample inlet and a breath sample outlet; 
 a sensing unit ( 2 ) located within the enclosure ( 1 ) and having an inlet connecting to i) the breath sample outlet of the first receptor unit when the first receptor unit is detachably secured to the enclosure and ii) the breath sample outlet of the second receptor unit when the second receptor unit is detachably secured to the enclosure, the inlet of the sensing unit ( 2 ) accepting the breath sample and providing a signal corresponding to a concentration of at least one volatile substance within said sample, said sensing unit ( 2 ) including 
 a sensor ( 9 ) providing a signal corresponding to the concentration of the at least one volatile substance within said sample, and 
 at least one of the group consisting of 
 a) a differential pressure sensor ( 16 ) for providing a dilution signal corresponding to the differential pressure exceeding a preset threshold, over a filter ( 12 ) exhibiting a flow resistance included within said sensing unit ( 2 ), said dilution signal indicating whether the sample is diluted or undiluted, and 
 b) a sensor element ( 8 ) responsive to CO 2  or water vapour to provide a non-dilution signal providing a dilution signal indicating whether the sample is diluted or undiluted; 
 a signal processing unit ( 3 ) configured to analyze said volatile substance to identify and quantify said volatile substance in said breath sample based on both said signal corresponding to the concentration and said dilution signal indicative of the dilution, 
 wherein said signal processing unit ( 3 ) is configured to perform at least two different calculations for the quantification, a first calculation for the screening operational mode and a second calculation for the operational mode with a higher accuracy than the screening operational mode, 
 wherein said signal processing unit ( 3 ) is configured to automatically display a result of a selected calculation, the selection being based on a result of said signal indicating the dilution of said sample by any in the group consisting of i) said threshold of differential pressure being exceeded or not, and ii) the CO 2  signal exceeding a normal alveolar concentration or not, and 
 wherein the dilution signal enables the breath analyzer to be automatically switched, in response to said dilution signal indicating the dilution of said sample, between i) the screening operational mode where said signal processing unit ( 3 ) performs the first calculation for the screening operational mode and ii) the operational mode where said signal processing unit ( 3 ) performs the second calculation, using a result of the first calculation, with the higher accuracy than the screening operational mode. 
 
     
     
       2. The breath analyzer according to  claim 1 , wherein, the sensor is further responsive to a tracer substance within said sample, and said calculation includes a degree of the dilution estimated by simultaneous determination of a concentration of the tracer substance within said sample. 
     
     
       3. The breath analyzer according to  claim 1 , wherein said at least one volatile substance is ethanol or methanol, acetone, carbon monoxide, carbon dioxide, ammonia, nitric oxides, and tracer substance as marker to distinguish between said breath and ambient air. 
     
     
       4. The breath analyzer according to  claim 1 , further comprising elements ( 12 ,  16 ) providing a signal indicative of tightness of connection between respiratory organs of said subject and said sensing unit ( 2 ), said elements ( 12 ,  16 ) including a well defined flow resistance ( 12 ) and a differential pressure sensor ( 16 ) having openings ( 16 ′,  16 ″) upstream and downstream of said flow resistance ( 12 ), said openings being directed perpendicular to a main flow direction of said sample. 
     
     
       5. The breath analyzer according to  claim 1 , wherein said sensing unit ( 2 ) includes a geometrically well defined measuring volume, the inlet ( 5 ) of which includes the connection to said receptor unit ( 4   a ,  4   b ), and a particle filter ( 12 ) for separation of liquid droplets and solid particles within said sample, an outlet of which is connected to ambient air, said measuring volume being smaller than 100 ml, said sensing unit ( 2 ) having small but distinctive resistance to air flow, said flow being controllable by a pump, a fan or a valve ( 10 ,  11 ). 
     
     
       6. The breath analyzer according to  claim 1 , wherein said sensing unit ( 2 ) generates a repetitive signal at a repetition frequency of 5 Hz or more, said repetitive signal corresponding to the concentration of said at least one volatile substance within a geometrically defined measuring volume. 
     
     
       7. The breath analyzer according to  claim 1 , wherein said sensing and signal processing units ( 2 ,  3 ) are based on catalytic measuring principle or based on transmission measurement of multiply reflected electromagnetic radiation against a surface with high reflectance within a defined measuring volume, whereby said analysis includes absorption within a defined wavelength interval for the determination of said at least one volatile substance, and for the determination of a tracer substance. 
     
     
       8. The breath analyzer according to  claim 1 , wherein said analyzer is contained within an enclosure ( 1 ) resistant to environmental stress, and including said sensing and analyzing units, a battery ( 13 ) for power source, a display ( 14 ) for indication of analysis results, a memory unit for storage of data, switches for data input, and means for data communication ( 15 ) to external equipment, said enclosure comprising an autonomous unit for sampling and immediate analysis. 
     
     
       9. The breath analyzer according to  claim 1 , wherein said enclosure ( 1 ) is resistant to environmental stress, and including said sensing and analyzing units, and said analyzer further includes a battery ( 13 ) for a power source, a display ( 14 ) for indication of analysis results, a memory unit for storage of data, switches for data input, and a dedicated connector for data communication ( 15 ) to external equipment, said enclosure comprising an autonomous unit for sampling and immediate analysis. 
     
     
       10. The breath analyzer according to  claim 2 , wherein the tracer substance to which the sensor is responsive is carbon dioxide or water vapor. 
     
     
       11. The breath analyzer according to  claim 3 , wherein the tracer substance to which the sensor is responsive is carbon dioxide or water vapor. 
     
     
       12. The breath analyzer according to  claim 1 , wherein said sensing and signal processing units ( 2 ,  3 ) are based on a catalytic measuring principle sensing said at least one volatile substance as ethyl alcohol, and determining a tracer substance as carbon dioxide. 
     
     
       13. The breath analyzer according to  claim 1 , wherein said sensing and signal processing units ( 2 ,  3 ) are based on transmission measurement of multiply reflected electromagnetic radiation against a surface with high reflectance within a defined measuring volume, whereby said analysis includes absorption within a defined wavelength interval of 9-10 um for the determination of said at least one volatile substance including ethyl alcohol, and another interval of 4.2-4.3 um for the determination of a tracer substance including carbon dioxide. 
     
     
       14. The breath analyzer according to  claim 1 , further comprising a fan that draws the breath sample into the inlet of the sensing unit. 
     
     
       15. A dual mode breath analyzer, comprising:
 a hand-held enclosure ( 1 ); 
 a battery power source; 
 switches for data input; 
 a sensing unit ( 2 ) included within the enclosure, the sensing unit ( 2 ) including an inlet ( 5 ) that accepts a breath sample, the sensing unit providing a signal corresponding to a concentration of a volatile substance within the breath sample, the sensing unit ( 2 ) including 
 a sensor ( 9 ) providing a signal corresponding to the concentration of the volatile substance within said sample, and 
 at least one of the group consisting of 
 a) a differential pressure sensor ( 16 ) for providing a dilution signal corresponding to the differential pressure exceeding a preset threshold, over a filter ( 12 ) exhibiting a flow resistance included within said sensing unit ( 2 ), said dilution signal indicating whether the sample is diluted or undiluted, an absence of the dilution signal indicating a non-dilution of the breath sample, and 
 b) a sensor element ( 8 ) responsive to CO 2  or water vapour to provide a dilution signal indicating whether the sample is diluted or undiluted; 
 a signal processing unit ( 3 ) located within the enclosure and coupled to the sensing unit, the signal processing unit configured to identify and quantify the volatile substance in the breath sample based on both i) said signal corresponding to the concentration of the volatile substance within the breath sample and ii) said signal indicative of the dilution of the volatile substance within the breath sample; and 
 a receptor unit that secures to the inlet ( 5 ) of sensing unit, the receptor unit for receiving the breath sample from a test subject, a first receptor unit including a contactless-mode receptor unit having a shape of a funnel ( 4   a ), scoop, cup or mug for contactlessly receiving the breath sample from the test subject in a contactless mode of the breath analyzer, and a second receptor unit ( 4   b ) having a tubular shape that receives the breath sample from the test subject in a contact mode of the breath analyzer, 
 wherein said dual mode breath analyzer is an autonomous unit for sampling and immediate analysis of said breath sample, 
 wherein the breath analyzer is further configured so that the dilution signal enables the breath analyzer to automatically switch from screening operational mode having the first receptor unit to the operational mode having the second receptor unit with the higher accuracy than the screening operational mode in response to said dilution signal indicating the dilution of said sample, and said signal processing unit ( 3 ) is configured to perform at least two different calculations for the quantification, a first calculation for the screening operational mode and a further second calculation, using a result of the first calculation, for the operational mode with the higher accuracy than the screening operational mode. 
 
     
     
       16. The breath analyzer according to  claim 15 , further comprising a fan within the sensing unit that draws the breath sample into the inlet of the sensing unit. 
     
     
       17. The dual mode breath analyzer according to  claim 1 , wherein the preset pressure threshold for the differential pressure sensor is 100 Pa. 
     
     
       18. The dual mode breath analyzer according to  claim 1 , further comprising a source ( 7 ) of electromagnetic radiation within the infrared (IR) wavelength range, and wherein the sensor element responsive to CO 2  or water vapour includes IR detectors equipped with band pass interference filters tuned to wavelength intervals which coincide with absorption peaks of the substances to be determined. 
     
     
       19. The dual mode breath analyzer according to  claim 1 , further comprising a source ( 7 ) of electromagnetic radiation within the infrared (IR) wavelength range, and wherein,
 the sensor providing a signal corresponding to the concentration of the at least one volatile substance and the sensor element responsive to CO 2  are comprised of a first IR detector equipped with band pass interference filter tuned to a wavelength interval which coincide with an absorption peak of the at least one volatile substance, and a second IR detector equipped with band pass interference filter tuned to a wavelength interval which coincide with an absorption peak of CO 2 . 
 
     
     
       20. A dual mode breath analyzer comprising:
 a receptor unit ( 4 ) for receiving a breath sample from a test subject, the receptor unit including a first receptor unit ( 4   a ) having the shape of a funnel ( 4   a ) scoop, cup or mug for receiving the breath sample from the test subject in a contactless mode of said dual mode breath analyzer, and a second receptor unit ( 4   b ) having a tubular shape for receiving the breath sample from the test subject in a contact mode of said dual mode breath analyzer, the contactless mode being a screening operational mode and the contact mode being an operational mode with a higher accuracy than the screening operational mode; 
 a sensing unit ( 2 ) having an inlet for accepting the breath sample, via a filter ( 12 ), from i) the first receptor unit ( 4   a ) when in the contactless mode of said dual mode breath analyzer, and ii) the second receptor unit ( 4   b ) when in the contact mode of said dual mode breath analyzer, said sensing unit ( 2 ) including 
 a) a differential pressure sensor ( 16 ) for providing a dilution signal corresponding to a differential pressure across the filter ( 12 ) exceeding a preset threshold, the differential pressure across the filter ( 12 ) measuring a flow resistance, said dilution signal indicating whether the sample is diluted or undiluted, 
 b) a sensor element ( 9 ) responsive to CO 2  concentration and arranged to provide a signal indicating the sample is undiluted when the CO 2  concentration exceeds a normal alveolar concentration, and 
 c) a sensor ( 8 ) providing a signal corresponding to a concentration of a volatile substance within said sample and indicating whether the sample is diluted or undiluted; 
 a signal processing unit ( 3 ) configured to analyze said volatile substance to identify and quantify said volatile substance in said breath sample based on both said signal corresponding to the concentration of the volatile substance and said dilution signal indicative of the dilution, 
 wherein said signal processing unit ( 3 ) is configured to perform at least two different calculations for the quantification, a first calculation for the screening operational mode and a second calculation for the operational mode with a higher accuracy than the screening operational mode, 
 wherein said signal processing unit ( 3 ) is configured to automatically display a result of a selected calculation, the selection being based on a result of said signal indicating the dilution of said sample based on i) whether or not said threshold of differential pressure is exceeded, and ii) whether or not the CO2 signal exceeds the normal alveolar concentration; and 
 wherein the dilution signal enables the breath analyzer to be automatically switched from the screening operational mode to the operational mode, using a result of the first calculation, with the higher accuracy than the screening operational mode in response to said dilution signal indicating the dilution of said sample.